The other two possible outcomes are the GOP maintaining control over the two chambers and the Democrats sweeping both the House and Senate.

The outcome of these elections has massive implications for investors as it will influence which policy initiatives Congress will pursue or will block. Some of the key areas that will be affected by these outcomes include drug pricing and banking regulation.

These results could also lead to more investigations into President Donald Trump.

But regardless of how the elections shake out, this is the best buying opportunity for investors before year-end, said Phil Blancato, CEO of Ladenburg Thalmann Asset Management.

“This is your entry point,” he said, adding that positive seasonal factors, including strong holiday sales, should boost markets higher before the end of 2018. “You might get some volatility in the next couple of days as the market absorbs the result, but you buy those dips. … Everything is telling you this is the time to buy” following the correction in October.

When government is divided like this — a split Congress and a Republican president — the S&P 500 averages a return of 12 percent annually, according to Bank of America Merrill Lynch.